President Trump confirmed Friday he is under investigation for the firing of former FBI director James Comey.

President Donald Trump acknowledged today that he is personally under investigation as part of a widening probe into alleged Russian meddling in last year's U.S. presidential race and possible collusion by his campaign, an inquiry that has cast a shadow over his five months in office. While the investigation had originally been focused on potential collusion between the Trump campaign and Russian Federation, the Post reported, the obstruction inquiry began after Trump fired Comey. Dick Durbin said Friday that President Donald Trump will put the country at the "brink of a constitutional crisis" if he fires special counsel Robert Mueller.

Trump criticized an unnamed "man who told me to fire ..."

It is unclear whether Ledgett had direct contact with Trump or other top officials about the Russian Federation probe, but he wrote an internal NSA memo documenting the president's phone call with Rogers, according to officials. A day later, Rosenstein appointed Mueller, who was at the helm of the Federal Bureau of Investigation during the September 11 attacks, as special counsel.

A source familiar with the Mueller investigation confirmed the Post report, saying an examination of possible obstruction of justice charges was "unavoidable" given Comey's testimony, although the issue may not become the main focus of the probe.

On the congressional side, most of the attention so far has been focused on a separate Senate Intelligence Committee investigation of Russian interference in the 2016 election and any possible collusion with associates of Trump or his campaign.

The investigation over possible obstruction of justice just adds to the scandal involving the president, with Donald Trump and his supporters claiming that he is a victim of a "witch hunt" created by his opponents and the so-called "fake news" media.

It quoted five people briefed on the requests and said those who have agreed to be interviewed are Daniel Coats, the director of national intelligence, Admiral Mike Rogers, head of the National Security Agency, and his recently departed deputy, Richard Ledgett. "They clearly don't have control over what he's tweeting and it has been long standing practice that when you're under investigation you don't attack publicly the investigators". Trump cited the memo in firing Comey.

"President Trump said prior that once he gets in he's going to kick the S-H-I-T out of the enemy". However, Trump later told NBC News' Lester Holt that he had already made a decision to fire Comey before that memo was written.

Starr's op-ed follows comments he made on CNN's "New Day" Thursday morning in which he said there is now no obstruction of justice case against Trump, based on the evidence that has been made public so far. Mr. Kushner previously volunteered to share with Congress what he knows about Russia-related matters.

Rosenstein was also the author of a letter in May to Trump, criticising the performance of FBI Director James Comey.

Moscow has denied USA intelligence agencies' conclusion that it interfered in last year's election campaign to try to tilt the vote in Trump's favor.

Several congressional panels are also investigating the Russian Federation issue, which has cast a shadow over the early months of Trump's presidency.

But Cornyn questioned the value of bringing Comey and others to hearings in the Judiciary Committee when they have already testified before the Intelligence Committee.